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.NoteUnfortunately, Illustrator provides no equivalent function to export paths for use inPhotoshop, nor can Photoshop open Illustrator documents from disk and interpretthem as paths.This means the Clipboard is the only way to take a path created oredited in Illustrator and use it in Photoshop.Cross- Only about half of Photoshop users own Illustrator.Meanwhile, close to 90 percentReferenceof Illustrator users own Photoshop.This is why I cover the special relationshipbetween Illustrator and Photoshop in depth in my Illustrator book, Real WorldIllustrator 9 (Berkeley, CA: Peachpit Press, 2000).Retaining transparent areas in an imageWhen you import an image into Illustrator, FreeHand, CorelDraw, QuarkXPress,PageMaker, InDesign, or some other object-oriented program, the image comes in asa rectangle with opaque pixels.Even if the image appeared partially transparent inPhotoshop on a layer, for example the pixels are filled with white or some othercolor in the receiving application.These same object-oriented applications, how-ever, enable you to establish a clipping path to mask portions of an image that youwant to appear transparent.Elements that lie inside the clipping path are opaque; Chapter 8 &' Selections and Paths379elements outside the clipping path are transparent.Photoshop enables you toexport an image in the EPS format with an object-oriented clipping path intact.Whenyou import the image into the object-oriented program, it appears premasked with aperfectly smooth perimeter, as illustrated by the clipped image in Figure 8-39.Figure 8-39: I drew one path around the perimeter of the skull and another around theeye socket.After defining the paths as clipping paths, I exported the image in the EPSformat, imported it into Illustrator, and set it against a black background for contrast.The following steps explain how to assign a set of saved paths as clipping paths.STEPS: Saving an Image with Clipping Paths1.Draw one or more paths around the portions of the image that you want toappear opaque.Areas outside the paths will be transparent.2.Save the paths.Double-click the Work Path item in the Paths palette, entera path name, and press Enter.(Try to use a name that will make sense threeyears from now when you have to revisit this document and determine whatthe heck you did.)3.Choose the Clipping Path command from the Paths palette menu, as shownin Figure 8-40.Photoshop displays the dialog box shown at the top of the fig-ure, asking you to select the saved paths you want to assign as the clippingpath.Remember, you can t make the Work Path a clipping path; you must saveit as a named path first. Part III &' Selections, Masks, and Filters380NoteIf you like, enter a value in the Flatness option box.This option enables you tosimplify the clipping paths by printing otherwise fluid curves as polygons.The Flatness value represents the distance between 0.2 and 100, in printerpixels that the polygon may vary from the true mathematical curve.Ahigher value leads to a polygon with fewer sides.This means it looks chunkier,but it also prints more quickly.I recommend a value of 3.Many experts sayyou can go as high as 7 when printing to an imagesetter without seeing thestraight edges.But I strongly suspect it depends on how much of a perfection-ist you are.Me? I like 3.Figure 8-40: Choose the Clipping Path command fromthe Paths palette menu (bottom) and then select thepath that you want to use from the Clipping Pathdialog box (top).4.Choose File ª' Save As and select Photoshop EPS from the Format pop-upmenu.Select the desired Preview and Encoding settings and then press Enter.Photoshop saves the EPS image with masked transparencies to disk.NotePageMaker and InDesign support clipping paths saved in the TIFF format.So if youplan on placing the image in PageMaker, you can save the image in TIFF instead ofEPS in Step 4.Figure 8-41 shows an enhanced version of the clipped skull from Figure 8-39.In addi-tion to exporting the image with clipping paths in the EPS format, I saved the pathsto disk by choosing File ª' Export ª' Paths to Illustrator.Inside Illustrator, I used theexported paths to create the outline around the clipped image.I also used them to Chapter 8 &' Selections and Paths381create the shadow behind the image.The white of the eyeball is a reduced version ofthe eye socket, as are the iris and pupil.The background features a bunch of flippedand reduced versions of the paths.This may look like a lot of work, but the onlydrawing required was the creation of the two initial Photoshop paths.Figure 8-41: It s amazing what you can accomplish by combiningscans edited in a painting program with smooth lines created in adrawing program.Be prepared for your images to grow by leaps and bounds when imported intoIllustrator.The EPS illustration shown in Figure 8-41 consumes six times as muchspace on disk as the original Photoshop image saved in the TIFF format.CautionWhen used in excess, clipping paths will present problems for the most sophisti-cated printing devices.You should use a clipping path only when it s absolutelynecessary and can t be avoided.If you want to place an image against a bitmappedbackground, for example, do it in Photoshop, not in Illustrator, QuarkXPress, or anyother application.This invariably speeds printing and may mean the differencebetween whether or not a file prints successfully.&' &' &' C H A P T E R99Masks andExtractions&' &' &' &'In This ChapterAn introduction toSelecting Via MasksmaskingMost Photoshop users don t use masks.If my personal experi-Painting inside aence is any indication, it s not only because masks seem com-selection outlineplicated but also because they strike most folks as being moretrouble than they re worth.Like nearly everyone, when I firstUsing the quick maskstarted using Photoshop, I couldn t even imagine a possiblemode to modifyapplication for a mask.I have my lasso tool and my magicselection outlineswand.If I m really in a rut, I can pull out my pen tool.Whatmore could I possibly want?Drawing gradientselections in the quickQuite a bit, as it turns out.Every one of the tools I just men-mask modetioned is only moderately suited to the task of selectingimages.The lasso tools let you create free-form selections, butCreating translucentnone of the tools not even the magnetic lasso can accountgradient arrowsfor differences in focus levels.The magic wand selects areas ofcolor, but it usually leaves important colors behind, and theUsing the Extractedges of its selection outlines often appear ragged and ugly.command to clip awayThe pen tool is extremely precise, but it results in mechanical the image backgroundoutlines that may appear incongruous with the naturalimagery they contain.Selecting images withthe Color RangecommandMasks offer all the benefits of the other tools.With masks, youcan create free-form selections, select areas of color, and gen-Saving a selectionerate amazingly precise selections.Masks also address all theoutline to a maskdeficiencies associated with the selection tools.They canchannelaccount for different levels of focus, they give you absolutecontrol over the look of the edges, and they create selectionsConverting channelsevery bit as natural as the image itself.into selectionsIn fact, a mask is the image itself.Masks use pixels to selectCreating a highlypixels.Masks are your way to make Photoshop see what youaccurate mask basedsee using the data inherent in the photograph [ Pobierz caÅ‚ość w formacie PDF ] |
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